Spas such as hot tubs have enjoyed increased popularity in recent years. Spas typically provide a means for bathers to relax in a controlled environment of warmth and gentle water massage.
FIG. 1 illustrates a conventional spa 10. A tub 12 is generally formed of rigid material and permanently mounted or fixed either in the ground or above the ground at a specific location. For circulating the water, a water pumping system 14 is provided which includes a pump 15 pulling water from the bathing chamber through submersed suctions or drains 16, and returning the water back to the bathing chamber by way of therapeutic pressure jets 18. This process is known in the industry as “hydrotherapy.” The jets typically push water out at a pressure of 8 to 15 psi per jet. The pumps typically range from 100 gallons per minute to 300 gallons per minute but can be as much as 450 gallons per minute per pump. Spas typically include one or more pumps depending on the size of the spa and the number of jets in the spa.
There have been numerous cases of serious injuries and deaths caused by high vacuum levels at a pool or spa's drain which holds an individual to the drain. Various attempts have been made for preventing injury to persons due to the high vacuum levels at the pool's drain in pools and spas.
For example, U.S. Pat. No. 7,820,041 issued to Hilton et al. discloses a drain cover designed for swimming pools, spas, whirlpools and the like that is non-flat and clover-shaped containing three or more “leaves” that provides for strengthened rigidity, and increased protection against hair and body entrapment.
U.S. Pat. No. 7,931,447 issued to Levin et al. discloses a drain safety and pump control device for pools and spas. The device includes a vacuum sensor for sensing a level of vacuum present in the suction conduit leading to the pumps. The vacuum level is monitored by a computer that controls a vent valve that can vent to atmosphere to reduce the vacuum exerted at a drain disposed at the bottom of the pool or spa.
U.S. Pat. No. 6,591,863 issued to Ruschell et al. discloses an adjustable pool safety valve for swimming pools that senses and then instantly relieves excessively high vacuum levels in the pool's drain line, such as when an individual becomes trapped by the suction at the pool's drain port which is connected to the drain line. The valve includes a spring biased mechanism which is tripped to relieve the high vacuum level in the pool's drain line and the suction at the drain port by bleeding air into the pool's drain line, causing the pump connected to the drain line to lose prime.
Swimming pools typically employ a skimmer in the upper part of the side of the pool that catches floating debris before it gets saturated and sinks to the bottom. A skimmer typically includes a basket, a lid, and a weir or floating door. A pipe attached to the bottom of the skimmer connects to the pool's filter pump. Water is pulled through the skimmer by the pump. The weir floats at the water level, causing the suction to speed up and pull in more of the debris. The debris gets stuck in the basket as the water goes into the filter and is cycled back into the pool. The typical flow rate though a skimmer is about 50 gallons per minute to about 75 gallons per minute. When the pump is shut off, the weir closes off the skimmer and keeps debris from coming out of the basket and back into the pool.
U.S. Pat. No. 7,300,576 issued to Blake discloses a swimming pool cleaning system having a pump, a first tube coupling a suction port of the pump in fluid communication with a main drain or mobile cleaning device which draws water and settled debris from the bottom of the pool, and a skimming device having a cylindrical body, an entrainment nozzle and a safety tube. The entrainment nozzle is coupled by a second tube to a coupling device which diverts a small portion of pool return water pumped from an outlet port of the pump. The safety tube connects the inside of the body of the skimmer above the waterline and above the debris trap to the inside of the body of the skimmer below the waterline the debris trap. Most of the pool return water is pumped into a rotary distribution valve, various outlets of which are connected to various pool cleaning heads embedded in an inner surface of the pool. A single low-horsepower pump produces simultaneous effective skimming and operation of embedded cleaning heads.
There is a need for further pools and spas, and more specifically, to low gravity fed water system for pools, spas, and the like, for reducing the likelihood of entrapment of a person's hair and body.